The present invention is concerned generally with the art of door opening and closing devices, and more particularly, an apparatus for automatically opening and closing a sliding door mounted on a structure.
It has been known for many years to open doors, such as garage doors, by initial vertical movement of the door along a track until the door reaches a radius in the track and begins horizontal movement at the top end of the door while the bottom end is still rising vertically. Ultimately, the door is typically opened until the entire door is substantially horizontally disposed, generally parallel with the floor of the garage. Actuation of a garage door along its track is typically accomplished by a small horsepower motorized unit. The motorized units typically drive a flexible member such as a belt along one or more pulleys to lift the door and cause the door to travel along the track. Once opened, the door may be closed by the motorized unit causing the flexible member to operate in a reverse direction, resulting in the door moving down the track and back to a closed position. Ordinarily, the motorized units are secured to the ceiling or to roof trusses of the garage or other structure on which the doors are mounted.
The known motorized units are typically operated by simply being plugged into an electrical outlet. The motorized unit may be caused to turn on by well-known means of a hand-held remote control transmitter which is set to a frequency that matches that of a receiver in the motorized unit. The hand-held remote control transmitter is usually battery powered and operates by simply pushing a button on the hand-held unit while within range of the receiver which starts the motorized unit and opens the door. Pushing the button a second time, after the door is fully opened, will cause the motorized unit to operate in a reverse direction thereby closing the door.
Other devices have been invented for assisting in the opening and closing of large doors. In many cases, the inventions have included a track upon which the door is slidably mounted and a trolley attached to the door that travels on the track.
These known devices have been secured to the outside of the building structure to facilitate installation and operation with a track on which the door(s) is mounted. Tracks are usually mounted on the outside of a building structure doorway. And, these known devices require direct interaction with the track on the building structure. This interaction further limits these devices in that the operator track must substantially match the door track in length which limits the travel of the door(s). These known devices require customization to fit the particular door track on location. The cost of the known devices plus installation costs are twice (or more) as expensive as the present invention. This is at least in part because the present invention does not directly interact with the door track, which eliminates the need for customization to mate with the door track.
The present invention is primarily intended for the operation of opening and closing doors that slide open in a horizontal direction. The present invention is useful in opening and closing sliding doors on barns, warehouses, hangers, and other structures. The present invention may be located inside the building structure so that it is not exposed to weather, vandalism, theft, or other calamity. A remote control transmitter may be used to open and close the door from outside the building structure in a manner like that used in association with typical garage door openers. The present invention works in association with the door track already installed when the door was hung. The present invention is designed to work in conjunction with any track upon which a door slides.
The present invention includes a motorized unit similar to that used on overhead garage door openers. The present invention further comprises a motorized unit that drives a flexible member, such as a chain, which is interconnected through one or more structural members and associated chain engagement means in association with the structural members, and means for changing the direction of the chain to cause the chain to travel in a continuous loop, to open and close the door without need for manual involvement to push or pull the door open and closed. The motorized unit of the present invention may be powered by conventional electrical means. The motorized unit may be adapted for staring and stopping by remote control transmitting and receiving means. The motorized unit drives a set of gears over which the chain or other flexible member passes. The motorized unit is associated with adjustment means for adjusting the amount of travel the chain or other flexible member will undertake when opening or closing a given door. A structural member is mounted to the door, and the means for changing the direction of the chain, such as an idler bracket assembly, is mounted to a portion of the structure on one side of the door opening opposite the side of the door opening where the motorized unit is mounted. The chain or other flexible member is driven by the motorized unit gear drive in a continuous loop fashion, through the door mounted structural member and through the far side wall mounted idler bracket, before returning to the motorized unit. As the chain moves in one direction (ordinarily clockwise or counterclockwise), the door opens, and as the chain moves in the opposite direction, the door closes. The present invention is designed to open and close a single sliding door, biparting single track doors, and biparting overlapping doors.
The present invention will be more thoroughly explained by the following drawings and detailed description.